Chain jack



Aug. 25, 1931. F. w. COFFING CHAIN JACK Filed 001;. 5. 1929 ATTORNEYJ'.

Patented Aug. 25, 1931 .PATEN T OFFICE FREDRICK W. 'COFFING, OFPERRYVILLE, INDIANA CHAIN JACK Application filed October 5, 1 29. SerialNo. 397,645.

This invention relates to a power device for association with. apparatussuch as pike poles, extension props or similar devices, al-

though not necessarily confined thereto.

provide a simplebut rugged multiple power construction adapted toreceive and elevate an article as indicated. T

i The chief feature of the invention consists 1o in providinga socketinthe form of a'tube and slidably mounting therein a plunger,

which is operatively associated with a flexible power member, such as achain, the movement of which causes plunger movement in 15, the socket.

Another feature of the invention consists in the provision of a hingearrangement between the base and the socket supported thereby and theaddition of a latch construction for detachably' locking same in anadjustediposition. V

The full nature of the invention will be understood from theaccompanying "drawings and the following description and claims:

Fig.1 is a side elevation of the invention parts being broken away"andshown in half section to illustrate the same'a'nd' other parts indetail." Fig. 2 is a'top plan view of the head. Fig. 3 isatransversesectional view taken on li'ne'3'-3 'of'Fig. 1 and in the direction ofthe arrows. Fig. 4 is a perspective view of the top of apike pole shownin the form of a gas p'ipewith the head mounted thereon; Fig. 5 is acentral sectional view through {a modified form of base.

In thedrawings indicates a base,'11 an elongated tubular socket orcolumn, which is telescopically received in ahead 12, having the annularstop portion 13. Flange 13 limits the telescopic movement between thesocket and the head. The head 12 includes a pair of outwardlyandoppos'itely extending ears 14, each of which includes an open- I aweb16, so that the lateral load is distributed throughout the length ofthe tubular portion of the head, which causes a lateral binding upon theentire length of the tubular socket included within the head. The'chiefobject of the invention is to The tubular socket is provided with a pairof oppositely positioned elongated slots 17,

which extend parallel to the axis. A plunger 18 includes a substantialcylindrical head portion, depending from which is a yoke comprising apair of ears 19 in spaced relation. 'Each ear includes an alignedopening 20that supports shaft 21, in turn rotatably supporting sprocketwheel 22. The diameter of this sprocket wheel is greater than theinternal diameter of the tubular socket so that wheel teeth 23 extendoutwardly into longitudinal slots 17.

' A chain anchorage 23 is mountedin one of the'openings 15 of the headand is suit ably connected as at 24 to one end of the chorages 23 and 27are shown of a detachable character the anchorages permanent character.

The chain operating mechanism is contained within the housing 26illustrated, and is operated bya hand lever 28. The sprocket chainengages the sprocket wheel 29, mounted may be of a in said housing andhaving the locking dog 80 associated therewith. The sprocket wheel 29 issupported by shaft'128 coaxial Withthe pivotally mounted lever 28. Shaft128 supports a ratchet 32 engageable by a pawl 33, pivotally supportedby. a lever 28 and movable therewith. The details of construction andoperation of this chain operating mechanism are illustrated. describedand claimed per se in the co-pending application entitled .Automaticreverse ratcheting hoist, Serial No. 889,956,'filed September 3, 1929.

It will be obvious from the foregoing that as the chain is drawnupwardly through the housing 26 the sprocket wheel therein rotatesthesocket enclosed sprocket 22. For every inch of chain travel theplunger 18 travels one half inch. The load that may be supported by theplunger also is double that which may be supported by the chain if itwere applied thereto as described in the beforementioned application. 7The chain, as described therein, may be freely pulled through thehousing 26 in either direction when not under load, so that theplungermay be freely. positioned'within the socket. Likewise, theplunger may be ad-' vanced under load step bystep' or may be low credstep by step: when under load, and s1nce the cha n operating mechanismrs of the nondropping character, the plunger'cannot be rigid with thetubular portion 11 but which herein is shown pivotally associatedtherewith. Base includes an ear 36 and the lower portion of the tube 11includes a footing 37 that receives the same and includes an ear 38,having an arcuate portion 39-. The two earsare coaXially mounted as at40 and the arcuate surface 39 of one bears upon the surface 41 of thebase so that the axle 40 does not entirely support the load. the pivot40 is a segmental curved rack 42, the teeth of which are adapted toreceive a locking tooth 43, carried by arm 44 pivotally supported at 45upon the base35. Arm 44 is extended as at 46 and the bell crank leverthus formed is normally tilted, such that tooth 43 'ative to the base35. 'maintains the bell crank in locking position.

en a es the arcuate rack 42 for lockin the tuh D D bular socket inpre-determined relation rel- The spring 47 normally The tubular housingll is adapted to re ceive a casing pipe pole 60, the bottom end of whichbears on the movable support or plunger 18 and the upper end of whichprojects beyond the central opening in the head I 12. Suitably mountedupon. as by being re ceivable by theopen end of the pipe is a capconstruction having an intermediate bearing portion 61 and a pair ofdiverging i wings 62 and 63. The cap 61 has a portion figure indicates abase plate and 111 indi- J cates the tubular standard. A cap or footing137 is suitably secured as at 1370; to the lower end of the'tubularstandard 111. The

-' cap 137 terminates in a semi-spherical or Coaxial with partiallyspherical base portion 141, and the same is apertured as at 142, andthrough said aperture extends a pivotal member 140. Suitably secured tothe base 110 by passing through the aperture 143 therein and mountingupon the lower end and in the recess 144 of said base apartiallysphericalfaced washer 145 is suitably secured as at 146. r

A complementary surface 147 is provided within the cap or foot 141 and acomplementary washer 148 bearsthereon by a spring 149 suitably supportedby the pivot forming a stem 140 through the washer and nut construction150 and 151 respectively.

"Fig. 1 illustrates a relatively adjustable but-fiXed-positionarrangement while- Fig. 5 illustrates a substantially universalarrangement." 7 r The invention claimed, is: 1.. In combination atubular member, a hoistanehorage near the upper end thereof,

"a unitary hoist capable of independent operation and detachably securedto the anchorage'and mcludmga chain, said member having a pair ofoppositely positioned slots extending. longitudinally of and for aconsiderable portion of the tubular member, said chain extending throughthe tubular member and through the slots and having one end anchoredtothe upper end of the tubular member opposite from the hoist anchorage, aload supporting member longitudinally slidable in the tubular member,and a cham engaging sprocket rotatably supported by and movable with theload supporting member and movable by said chain for moving the loadsupporting member.

2. In combination a base, a tubular member vpivotally connected thereto,a hoist anchorage near the upper end thereof, a unitary hoist capable ofindependent operation and detachablysecured to the anchorage andincluding 'a chain, said member having a pair of oppositely positionedslots extending longitudinallyof and for a considerable portion. of thetubular member, said chain extending through the tubular member andthrough the slots and having one end anchored to the upper end of thetubular member opposite from the hoist anchorage, a load supportingmember longitudinally slidable in the tubular member, and a chainengaging sprocket rotatably supported by and movable with the g loadsupporting member and movable by said chain for moving the loadsupporting memher, the axis ofpivotalmovement being parallel to thesprocket axisl I 3.1n combination, a base, a tubular member pivotallyconnected thereto, a hoist anchora'ge near the upper end thereof, aunitary hoist'capable of independent operation and detachably secured tothe anchorage and including a chain, said member having a pair ofoppositely positionedslots extending longitudinally of and foraconsiderable portion of the tubular member, said chain extending throughthe tubular memberand through the slots and having one end anchored tothe 11pper end of the tubular member opposite from the hoist anchorage,a load-supporting member longitudinally slidable in the tubular membenachain-engaging sprocket rotatably supported by and movable with theload-supporting member and movable by said chain for moving theload-supporting member, the axis of pivotal movement being parallel tothe sprocket axis, and means for yieldingly locking thetubular member tothe base in an adjusted tilted position.

In Witness whereof, I my signature;

' FREDBICK W. COFFING.

have hereunto afiixed

